When you are asked to update the description of a cost center, you must log in English. For other changes you can log in your language

Start the transaction using the menu path or transaction code 

Enter the code of the cost center you want to update

and 

Select the period by clicking on 

Enter the validity date of the change and click on 

Perform the change and save the cost center by clicking 

If you want to update the description in another language, you must log in the language requested